feat(ui): context- and state-aware bottom keybinding strip (#27)

Per ADR-0051 (closing issue #27): the bottom status line is now a
keystrokes-only, state-selected strip. A pure status_bar_bindings()
picks the binding set by priority (first match wins):

  sidebar focus   → Ctrl-O next pane · ↑↓/PgUp/PgDn scroll · Esc input
  completion live → Tab/Shift-Tab cycle · Esc cancel · Enter run
  history nav     → ↑↓ browse · Esc clear · Enter run
  editing         → Esc clear · Ctrl-A/E home/end · Ctrl-W del word · Enter run
  default (empty) → Ctrl-O sidebar · Tab complete · ↑ history · Enter run

The editing state surfaces the #29 readline keys (ADR-0049's deferred
advertisement). Typed-command words (mode advanced/simple, the ':'
one-shot) and Ctrl-C quit leave the strip; simple mode's empty-input
hint gains a '`mode advanced` for SQL' pointer (advanced mode shows
none — a switcher knows the way back, and help covers it).

Mechanism: status_bar_bindings + a thin renderer (unit-testable);
App::is_browsing_history() exposes the private history_cursor; the mode
pointer lives in resolve_hint_lines. Catalog: 12 new shortcut labels +
panel.hint_mode_advanced (en-US.yaml + keys.rs, validator 1:1), 5 dead
strip strings removed.

Forks user-chosen: editing state shows #29 keys; quit omitted; no
width-drop machinery (longest strip ~65 cols fits; a width-budget test
keeps it lean). Modal-aware strip is OOS (pre-existing). Tests: 9
Tier-1 unit (per-state key sets, width budget, mode pointer), 1 Tier-3
rewritten, 15 full-panel snapshots re-accepted (reviewed). 2467 pass /
0 fail / 0 skip, clippy clean.

docs/adr/0051-context-state-aware-keybinding-strip.md

@@ -0,0 +1,147 @@
+# ADR-0051: Bottom keybinding strip — context- and state-aware
+
+## Status
+
+**Accepted 2026-06-13 (issue #27).** Closes Gitea **#27**. All forks
+below were escalated to the user and user-chosen before any code was
+written; to be implemented test-first. Builds on ADR-0046 (nav focus),
+ADR-0003 (input modes), ADR-0049 (the #29 readline keys this strip now
+advertises), and ADR-0022 (the Tab-completion memo).
+
+## Context
+
+The bottom status line (`render_status_bar`, `ui.rs`) mixed keystrokes
+with typed-command words: `Enter submit · : advanced once · mode
+advanced switch · Ctrl-C quit`. That is redundant — the hint panel
+already teaches `help` and `Enter` when the input is empty — and it is
+static apart from a three-way mode branch, so it never reflects what the
+user can actually do *right now* (navigating the sidebar, cycling a
+completion, browsing history, editing a line).
+
+Issue #27: repurpose the line as a **keybindings-only** strip that is
+**context-sensitive to nav focus** and **state-aware of the current
+transient interaction**, and move mode discovery into the empty-input
+hint.
+
+## Decision
+
+### 1. The strip is keybindings-only and state-selected
+
+A single pure function `status_bar_bindings(app) -> Vec<Binding>`
+computes the strip from app state; `render_status_bar` is a thin
+renderer over it (so the binding sets are unit-testable without a
+Frame). `history_cursor` is private to `App`, so a small
+`pub fn is_browsing_history(&self) -> bool` accessor exposes the
+history-navigation predicate; `mode` / `nav_focus` / `last_completion`
+are already `pub` and `effective_mode()` is a `pub` method. The state is
+chosen by **priority — first match wins**:
+
+| Priority | State (predicate) | Strip |
+|---|---|---|
+| 1 | **Sidebar focus** (`nav_focus` in a sidebar) | `Ctrl-O next pane · ↑↓/PgUp/PgDn scroll · Esc input` |
+| 2 | **Completion memo live** (`last_completion.is_some()`) | `Tab/Shift-Tab cycle · Esc cancel · Enter run` |
+| 3 | **History navigation** (`history_cursor.is_some()`) | `↑↓ browse · Esc clear · Enter run` |
+| 4 | **Editing** (Input focus, input non-empty) | `Esc clear · Ctrl-A/E home/end · Ctrl-W del word · Enter run` |
+| 5 | **Default** (Input focus, input empty) | `Ctrl-O sidebar · Tab complete · ↑ history · Enter run` |
+
+Priority order matters: a completion memo or history navigation is a
+non-empty-input situation, so states 2 and 3 must precede state 4. The
+sidebar overlay occludes the input entirely (ADR-0046), so state 1 wins
+outright.
+
+### 2. Mode discovery moves off the strip, into the empty-input hint
+
+The typed-command advertisements (`mode advanced` / `mode simple`
+switch, the `:` one-shot) leave the strip — they are not keystrokes.
+Mode discovery moves to the **empty-input hint** (`resolve_hint_lines`'s
+`(None, None)` arm), in **simple mode only**:
+
+- **Simple:** `… · \`mode advanced\` for SQL`
+- **Advanced (persistent):** no pointer.
+
+The pointer omits the verb "type" — the surrounding prompt already
+implies it (we don't say "type `help`" either). Advanced mode shows
+**no** pointer (user decision, post-trial): a user who switched into
+advanced mode knows how they got there, and `help` covers the way back —
+a "switch back" pointer only reads naturally in the moment right after
+switching, so it earns its space poorly.
+
+The one-shot advanced state's old `Backspace cancel one-shot` label is
+**subsumed** by the editing state (the input is non-empty in one-shot;
+Esc-clear and Backspace both cancel it). No behaviour is lost — only the
+dedicated label.
+
+### 3. Width: no drop machinery; a budget test instead
+
+The longest strip (state 4, editing) is ≈ **65 display columns**, which
+fits every supported width (90-col screencasts, 80-col terminals) with
+margin — so the priority-drop / abbreviation machinery considered would
+never trigger and is not built (user-confirmed). Ratatui's existing
+**clip-at-edge** is the trivial fallback for pathologically narrow
+(< 65-col) terminals. Instead, a **width-budget unit test** pins the
+longest rendered strip within an 80-col budget, keeping the strip lean
+*by construction* — a future over-long strip fails the test rather than
+silently clipping in a cast.
+
+## Forks (all user-chosen)
+
+- **Editing state — yes:** when the input has text, surface the #29
+  readline keys (Esc-clear, Ctrl-A/E, Ctrl-W); the strip stays lean
+  (nav/complete/history) when empty. (vs not advertising the #29 keys.)
+- **`Ctrl-C quit` — omitted** from the strip (vs always shown): quit is
+  a near-universal convention; omitting it keeps the strips lean and
+  matches the issue's sketch.
+- **Width — budget test, no drop logic** (vs graceful priority-drop /
+  abbreviation): the strips fit at supported widths, so the machinery
+  would be dead weight (user's own observation).
+
+## Consequences
+
+- The strip now teaches the keys for the *current* situation; learners
+  see `Tab/Shift-Tab cycle` exactly while cycling, the editing keys
+  exactly while editing, etc.
+- The #29 readline keys (ADR-0049) gain their on-screen advertisement,
+  closing that ADR's deferred item.
+- 15 existing full-panel insta snapshots churn (the bottom line — and,
+  on empty-input views, the hint pointer — changes in every one,
+  including the rebuild-confirm modal view, whose modal box is itself
+  unchanged); each diff was reviewed, not blind-accepted.
+- `requirements.md` is unaffected (an ADR-tracked UI refinement); the
+  change is cross-referenced from the commit + this ADR.
+
+## Tests
+
+- **Tier-1 (`ui.rs` unit):** `status_bar_bindings` returns the expected
+  key set for each of the five states (sidebar, completion-live,
+  history-nav, editing, default) — the completion/history states driven
+  through real key events (`update`) so the predicate transitions are
+  exercised, the others by setting `App` fields; plus the width-budget
+  assertion across states. (Per-state coverage is these unit tests, not
+  snapshots — a one-line strip is asserted more precisely by its exact
+  key list than by a full-panel snapshot.)
+- **Tier-1:** the empty-input hint appends the correct mode pointer in
+  Simple vs Advanced, and does **not** append it when an ambient hint is
+  showing (non-empty input).
+- **Tier-3 (`walking_skeleton`):** the old `status_bar_lists_quit_and_
+  submit_in_all_modes` (which asserted the pre-ADR strip) is rewritten +
+  renamed to assert the keystroke-only, state-aware strip end-to-end
+  through the real render path (default → editing transition).
+- **Tier-2 (insta):** the 15 full-panel snapshots re-accepted (each diff
+  reviewed — strip line and/or hint pointer only).
+
+## Out of scope
+
+- **Modal-aware strip.** While a modal is open (load picker, rebuild /
+  undo confirm) it owns the keyboard and carries its own in-box key
+  hints; the bottom strip under a modal computes from input state
+  exactly as it does today (modals render *over* the status bar). This
+  issue does not redesign the modal case — pre-existing behaviour,
+  unchanged and not worsened.
+- A persistent/togglable help overlay listing *all* keys (the strip is a
+  contextual subset, not a cheatsheet).
+- Per-key colour theming beyond the existing key/label/separator styles.
+- Localisation of the new label strings beyond adding catalog entries.
+- The remaining I1b kill keys' (Ctrl-K/Ctrl-U) advertisement — the
+  editing strip shows the highest-value subset (Esc/Ctrl-A/E/Ctrl-W) to
+  stay within the width budget; Ctrl-K/U remain unadvertised muscle
+  memory.

src/app.rs

@@ -646,6 +646,17 @@ impl App {
         }
     }
 
+    /// Whether the user is currently browsing a recalled history entry
+    /// (Up/Down navigation, unedited). Exposes the private
+    /// `history_cursor` predicate so the context-aware status strip
+    /// (ADR-0051) can select its history-navigation state. Editing the
+    /// recalled line ends navigation (`cancel_history_navigation`), so
+    /// this is `false` again the moment the user types.
+    #[must_use]
+    pub const fn is_browsing_history(&self) -> bool {
+        self.history_cursor.is_some()
+    }
+
     /// The input view the **live-feedback** walkers (completion, ambient
     /// hint, validity verdict, highlight overlays) should see, plus the
     /// byte offset stripped from the front and the cursor mapped into the

src/friendly/keys.rs

@@ -446,6 +446,7 @@ pub const KEYS_AND_PLACEHOLDERS: &[(&str, &[&str])] = &[
     ("undo.redo_failed", &["error"]),
     // ---- Status bar + panels ----
     ("panel.hint_empty", &[]),
+    ("panel.hint_mode_advanced", &[]),
     ("panel.hint_title", &[]),
     ("panel.output_title", &[]),
     ("panel.relationships_empty", &[]),
@@ -462,18 +463,25 @@ pub const KEYS_AND_PLACEHOLDERS: &[(&str, &[&str])] = &[
     ("save.title_as", &[]),
     ("save.title_save", &[]),
     // ---- Shortcut hint labels ----
-    ("shortcut.advanced_once", &[]),
     ("shortcut.back_to_list", &[]),
+    ("shortcut.browse", &[]),
     ("shortcut.browse_path", &[]),
     ("shortcut.cancel", &[]),
-    ("shortcut.cancel_one_shot", &[]),
+    ("shortcut.clear", &[]),
+    ("shortcut.complete", &[]),
     ("shortcut.confirm", &[]),
+    ("shortcut.cycle", &[]),
+    ("shortcut.del_word", &[]),
+    ("shortcut.history", &[]),
+    ("shortcut.home_end", &[]),
     ("shortcut.load", &[]),
+    ("shortcut.nav", &[]),
+    ("shortcut.next_pane", &[]),
     ("shortcut.no", &[]),
-    ("shortcut.quit", &[]),
+    ("shortcut.run", &[]),
+    ("shortcut.scroll", &[]),
     ("shortcut.select", &[]),
-    ("shortcut.submit", &[]),
+    ("shortcut.to_input", &[]),
-    ("shortcut.switch", &[]),
     ("shortcut.yes", &[]),
     // ---- mode / messages banners ----
     ("messages.set_short", &[]),

src/friendly/strings/en-US.yaml

@@ -883,14 +883,21 @@ panel:
   relationships_title: "Relationships"
   relationships_empty: "(none)"
   hint_empty: "Type a command — press Tab for options, `help` for a list"
+  # Mode-discovery pointer appended to the empty-input hint in SIMPLE
+  # mode (ADR-0051): the `mode advanced` switch left the keybinding
+  # strip, so the hint advertises it. Leading separator continues the
+  # prompt line. Advanced mode shows no pointer — users know how they
+  # got there, and `help` covers the way back.
+  hint_mode_advanced: " · `mode advanced` for SQL"
   # Panel titles for the output and hint panels (rendered inside
   # the rounded border, hence the leading/trailing space).
   output_title: "Output"
   hint_title: "Hint"
 
 # ---- Shortcut hints (paired with key names in the bottom bar) -------
+# The bottom strip is keystrokes-only and state-aware (ADR-0051). Labels
+# pair with a key name in the renderer (e.g. `Enter` + `run`).
 shortcut:
-  submit: "submit"
   confirm: "confirm"
   cancel: "cancel"
   yes: "Yes"
@@ -899,10 +906,19 @@ shortcut:
   select: "select"
   browse_path: "browse path"
   back_to_list: "back to list"
-  switch: "switch"
+  # Status-strip labels (ADR-0051, issue #27).
-  advanced_once: "advanced once"
+  run: "run"
-  cancel_one_shot: "cancel one-shot"
+  nav: "sidebar"
-  quit: "quit"
+  next_pane: "next pane"
+  scroll: "scroll"
+  to_input: "input"
+  cycle: "cycle"
+  browse: "browse"
+  clear: "clear"
+  complete: "complete"
+  history: "history"
+  home_end: "home/end"
+  del_word: "del word"
 
 # ---- mode / messages banners (app-level commands) -------------------
 mode:

src/snapshots/rdbms_playground__ui__tests__default_advanced_dark.snap

@@ -1,6 +1,6 @@
 ---
 source: src/ui.rs
-assertion_line: 2326
+assertion_line: 2836
 expression: snapshot
 ---
 ╭ Output ──────────────────────────────────────────────────────────────────────╮
@@ -26,4 +26,4 @@ expression: snapshot
 │                                                                              │
 ╰──────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                           
-Enter submit  ·  mode simple switch  ·  Ctrl-C quit
+Ctrl-O sidebar  ·  Tab complete  ·  ↑ history  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__default_simple_dark.snap

@@ -1,6 +1,6 @@
 ---
 source: src/ui.rs
-assertion_line: 2309
+assertion_line: 2819
 expression: snapshot
 ---
 ╭ Output ──────────────────────────────────────────────────────────────────────╮
@@ -22,8 +22,8 @@ expression: snapshot
 │                                                                              │
 ╰──────────────────────────────────────────────────────────────────────────────╯
 ╭ Hint ────────────────────────────────────────────────────────────────────────╮
-│Type a command — press Tab for options, `help` for a list                     │
+│Type a command — press Tab for options, `help` for a list · `mode advanced`   │
-│                                                                              │
+│for SQL                                                                       │
 ╰──────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                           
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·  Ctrl-C quit
+Ctrl-O sidebar  ·  Tab complete  ·  ↑ history  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__default_simple_light.snap

@@ -1,6 +1,6 @@
 ---
 source: src/ui.rs
-assertion_line: 2317
+assertion_line: 2827
 expression: snapshot
 ---
 ╭ Output ──────────────────────────────────────────────────────────────────────╮
@@ -22,8 +22,8 @@ expression: snapshot
 │                                                                              │
 ╰──────────────────────────────────────────────────────────────────────────────╯
 ╭ Hint ────────────────────────────────────────────────────────────────────────╮
-│Type a command — press Tab for options, `help` for a list                     │
+│Type a command — press Tab for options, `help` for a list · `mode advanced`   │
-│                                                                              │
+│for SQL                                                                       │
 ╰──────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                           
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·  Ctrl-C quit
+Ctrl-O sidebar  ·  Tab complete  ·  ↑ history  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__demo_badge_and_caption_stacked_90x26.snap

@@ -1,5 +1,6 @@
 ---
 source: src/ui.rs
+assertion_line: 3442
 expression: snapshot
 ---
 ╭ Output ────────────────────────────────────────────────────────────────────────────────╮
@@ -23,8 +24,8 @@ expression: snapshot
 │                                                                                        │
 ╰────────────────────────────────────────────────────────────────────────────────────────╯
 ╭ Hint ──────────────────────────────────────────────────────────────────────────────────╮
-│Type a command — press Tab for options, `help` for a list                               │
+│Type a command — press Tab for options, `help` for a list · `mode advanced` for SQL     │
 │                                                                                        │
 ╰────────────────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                                     
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·  Ctrl-C quit
+Ctrl-O sidebar  ·  Tab complete  ·  ↑ history  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__demo_badge_enter_light_90x26.snap

@@ -1,5 +1,6 @@
 ---
 source: src/ui.rs
+assertion_line: 3388
 expression: snapshot
 ---
 ╭ Output ────────────────────────────────────────────────────────────────────────────────╮
@@ -23,8 +24,8 @@ expression: snapshot
 │                                                                                        │
 ╰────────────────────────────────────────────────────────────────────────────────────────╯
 ╭ Hint ──────────────────────────────────────────────────────────────────────────────────╮
-│Type a command — press Tab for options, `help` for a list                               │
+│Type a command — press Tab for options, `help` for a list · `mode advanced` for SQL     │
 │                                                                                        │
 ╰────────────────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                                     
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·  Ctrl-C quit
+Ctrl-O sidebar  ·  Tab complete  ·  ↑ history  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__demo_badge_tab_dark_90x26.snap

@@ -1,5 +1,6 @@
 ---
 source: src/ui.rs
+assertion_line: 3378
 expression: snapshot
 ---
 ╭ Output ────────────────────────────────────────────────────────────────────────────────╮
@@ -23,8 +24,8 @@ expression: snapshot
 │                                                                                        │
 ╰────────────────────────────────────────────────────────────────────────────────────────╯
 ╭ Hint ──────────────────────────────────────────────────────────────────────────────────╮
-│Type a command — press Tab for options, `help` for a list                               │
+│Type a command — press Tab for options, `help` for a list · `mode advanced` for SQL     │
 │                                                                                        │
 ╰────────────────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                                     
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·  Ctrl-C quit
+Ctrl-O sidebar  ·  Tab complete  ·  ↑ history  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__demo_caption_dark_90x26.snap

@@ -1,5 +1,6 @@
 ---
 source: src/ui.rs
+assertion_line: 3431
 expression: snapshot
 ---
 ╭ Output ────────────────────────────────────────────────────────────────────────────────╮
@@ -23,8 +24,8 @@ expression: snapshot
 │                                                                                        │
 ╰────────────────────────────────────────────────────────────────────────────────────────╯
 ╭ Hint ──────────────────────────────────────────────────────────────────────────────────╮
-│Type a command — press Tab for options, `help` for a list                               │
+│Type a command — press Tab for options, `help` for a list · `mode advanced` for SQL     │
 │                                                                                        │
 ╰────────────────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                                     
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·  Ctrl-C quit
+Ctrl-O sidebar  ·  Tab complete  ·  ↑ history  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__demo_caption_wrapped_90x26.snap

@@ -1,5 +1,6 @@
 ---
 source: src/ui.rs
+assertion_line: 3457
 expression: snapshot
 ---
 ╭ Output ────────────────────────────────────────────────────────────────────────────────╮
@@ -23,8 +24,8 @@ expression: snapshot
 │                                                                                        │
 ╰────────────────────────────────────────────────────────────────────────────────────────╯
 ╭ Hint ──────────────────────────────────────────────────────────────────────────────────╮
-│Type a command — press Tab for options, `help` for a list                               │
+│Type a command — press Tab for options, `help` for a list · `mode advanced` for SQL     │
 │                                                                                        │
 ╰────────────────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                                     
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·  Ctrl-C quit
+Ctrl-O sidebar  ·  Tab complete  ·  ↑ history  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__highlighted_input_all_token_classes_dark.snap

@@ -1,6 +1,6 @@
 ---
 source: src/ui.rs
-assertion_line: 2369
+assertion_line: 2880
 expression: snapshot
 ---
 ╭ Output ──────────────────────────────────────────────────────────────────────╮
@@ -26,4 +26,4 @@ expression: snapshot
 │insert into <Table> [(<col>[, ...])] [values] (<value>[, ...])                │
 ╰──────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                           
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·  Ctrl-C quit
+Esc clear  ·  Ctrl-A/E home/end  ·  Ctrl-W del word  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__nav_overlay_relationships_focused_dark.snap

@@ -1,6 +1,6 @@
 ---
 source: src/ui.rs
-assertion_line: 2967
+assertion_line: 3347
 expression: snapshot
 ---
 ╭ Tables ───────────────────────────────────╮ ─────────────────────────────────╮
@@ -22,8 +22,8 @@ expression: snapshot
 ╰───────────────────────────────────────────╯                                  │
 ╭ Relationships ────────────────────────────╮ ─────────────────────────────────╯
 │Customers_Orders                           │ ─────────────────────────────────╮
-│  Customers.id ->                          │ ` for a list                     │
+│  Customers.id ->                          │ ` for a list · `mode advanced`   │
 │    Orders.customer_id                     │                                  │
 ╰───────────────────────────────────────────╯ ─────────────────────────────────╯
 Project: Term Planner                                                           
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·  Ctrl-C quit
+Ctrl-O next pane  ·  ↑↓/PgUp/PgDn scroll  ·  Esc input

src/snapshots/rdbms_playground__ui__tests__one_shot_advanced_dark.snap

@@ -1,6 +1,6 @@
 ---
 source: src/ui.rs
-assertion_line: 2385
+assertion_line: 2896
 expression: snapshot
 ---
 ╭ Output ──────────────────────────────────────────────────────────────────────╮
@@ -26,4 +26,4 @@ expression: snapshot
 │                                                                              │
 ╰──────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                           
-Enter submit  ·  Backspace cancel one-shot  ·  Ctrl-C quit
+Esc clear  ·  Ctrl-A/E home/end  ·  Ctrl-W del word  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__populated_with_table_dark.snap

@@ -1,6 +1,6 @@
 ---
 source: src/ui.rs
-assertion_line: 2679
+assertion_line: 3099
 expression: snapshot
 ---
 ╭ Tables ──────────────────╮╭ Output ────────────────────────────────────────────────────────────────────────╮
@@ -22,8 +22,8 @@ expression: snapshot
 ╰──────────────────────────╯│                                                                                │
 ╭ Relationships ───────────╮╰────────────────────────────────────────────────────────────────────────────────╯
 │(none)                    │╭ Hint ──────────────────────────────────────────────────────────────────────────╮
-│                          ││Type a command — press Tab for options, `help` for a list                       │
+│                          ││Type a command — press Tab for options, `help` for a list · `mode advanced`     │
-│                          ││                                                                                │
+│                          ││for SQL                                                                         │
 ╰──────────────────────────╯╰────────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                                                         
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·  Ctrl-C quit
+Ctrl-O sidebar  ·  Tab complete  ·  ↑ history  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__rebuild_confirm_modal_dark.snap

@@ -1,6 +1,6 @@
 ---
 source: src/ui.rs
-assertion_line: 2399
+assertion_line: 2909
 expression: snapshot
 ---
 ╭ Output ──────────────────────────────────────────────────────────────────────╮
@@ -22,8 +22,8 @@ expression: snapshot
 │                                                                              │
 ╰──────────────────────────────────────────────────────────────────────────────╯
 ╭ Hint ────────────────────────────────────────────────────────────────────────╮
-│Type a command — press Tab for options, `help` for a list                     │
+│Type a command — press Tab for options, `help` for a list · `mode advanced`   │
-│                                                                              │
+│for SQL                                                                       │
 ╰──────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                           
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·  Ctrl-C quit
+Ctrl-O sidebar  ·  Tab complete  ·  ↑ history  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__relationships_panel_dark.snap

@@ -1,6 +1,6 @@
 ---
 source: src/ui.rs
-assertion_line: 2789
+assertion_line: 3209
 expression: snapshot
 ---
 ╭ Tables ──────────────────╮╭ Output ────────────────────────────────────────────────────────────────────────╮
@@ -22,8 +22,8 @@ expression: snapshot
 ╰──────────────────────────╯│                                                                                │
 ╭ Relationships ───────────╮╰────────────────────────────────────────────────────────────────────────────────╯
 │Customers_Orders          │╭ Hint ──────────────────────────────────────────────────────────────────────────╮
-│  Customers.id ->         ││Type a command — press Tab for options, `help` for a list                       │
+│  Customers.id ->         ││Type a command — press Tab for options, `help` for a list · `mode advanced`     │
-│    Orders.customer_id    ││                                                                                │
+│    Orders.customer_id    ││for SQL                                                                         │
 ╰──────────────────────────╯╰────────────────────────────────────────────────────────────────────────────────╯
 Project: Term Planner                                                                                         
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·  Ctrl-C quit
+Ctrl-O sidebar  ·  Tab complete  ·  ↑ history  ·  Enter run

src/snapshots/rdbms_playground__ui__tests__two_row_input_dark.snap

@@ -1,6 +1,6 @@
 ---
 source: src/ui.rs
-assertion_line: 2265
+assertion_line: 2616
 expression: snapshot
 ---
 ╭ Output ──────────────────────────────────────────────────╮
@@ -46,4 +46,4 @@ expression: snapshot
 │with `mode advanced`, or prefix the line with `:` to run… │
 ╰──────────────────────────────────────────────────────────╯
 Project: Term Planner                                       
-Enter submit  ·  : advanced once  ·  mode advanced switch  ·
+Esc clear  ·  Ctrl-A/E home/end  ·  Ctrl-W del word  ·  Ente

src/ui.rs

@@ -1694,7 +1694,19 @@ fn resolve_hint_lines(
         (None, Some(crate::input_render::AmbientHint::Candidates { items, selected })) => {
             vec![render_candidate_line(&items, selected, inner, theme)]
         }
-        (None, None) => prose(&crate::t!("panel.hint_empty")),
+        // Empty input: the base prompt, plus — in simple mode only — a
+        // pointer to advanced mode (ADR-0051, issue #27), since the
+        // `mode advanced` switch left the keybinding strip. Advanced
+        // mode shows no pointer: users know how they reached it, and
+        // `help` covers the way back. (One-shot never reaches here — its
+        // `:` makes the input non-empty → ambient path.)
+        (None, None) => {
+            let mut text = crate::t!("panel.hint_empty");
+            if matches!(app.effective_mode(), EffectiveMode::Simple) {
+                text.push_str(&crate::t!("panel.hint_mode_advanced"));
+            }
+            prose(&text)
+        }
     }
 }
 
@@ -1845,6 +1857,63 @@ fn render_candidate_line(
     Line::from(spans)
 }
 
+/// The keybinding strip is keystrokes-only and **state-selected**
+/// (ADR-0051, issue #27): it advertises the keys for the user's *current*
+/// interaction, chosen by priority — first matching state wins.
+///
+/// Returns `(key, label)` pairs (label localised via `t!`); the renderer
+/// is a thin span builder over this list, so the binding sets are
+/// unit-testable without a `Frame`. Mode-switch / `:` advertisements
+/// deliberately leave the strip — they are typed commands, not
+/// keystrokes — and move to the empty-input hint (`resolve_hint_lines`).
+fn status_bar_bindings(app: &App) -> Vec<(&'static str, String)> {
+    // 1. Sidebar focus (Ctrl-O): the input is occluded by the overlay,
+    //    so the panel-scroll keys win outright (ADR-0046).
+    if app.nav_focus.in_sidebar() {
+        return vec![
+            ("Ctrl-O", crate::t!("shortcut.next_pane")),
+            ("↑↓/PgUp/PgDn", crate::t!("shortcut.scroll")),
+            ("Esc", crate::t!("shortcut.to_input")),
+        ];
+    }
+    // 2. A live Tab-completion memo (ADR-0022): cycling keys. Pressing
+    //    Up clears the memo, so this never co-occurs with state 3.
+    if app.last_completion.is_some() {
+        return vec![
+            ("Tab/Shift-Tab", crate::t!("shortcut.cycle")),
+            ("Esc", crate::t!("shortcut.cancel")),
+            ("Enter", crate::t!("shortcut.run")),
+        ];
+    }
+    // 3. Browsing recalled history (unedited): browse keys. Editing the
+    //    recalled line ends navigation, dropping to state 4.
+    if app.is_browsing_history() {
+        return vec![
+            ("↑↓", crate::t!("shortcut.browse")),
+            ("Esc", crate::t!("shortcut.clear")),
+            ("Enter", crate::t!("shortcut.run")),
+        ];
+    }
+    // 4. Editing — the input has text: surface the readline edit keys
+    //    (ADR-0049). The highest-value subset stays within the width
+    //    budget; Ctrl-K/U remain unadvertised muscle memory.
+    if !app.input.is_empty() {
+        return vec![
+            ("Esc", crate::t!("shortcut.clear")),
+            ("Ctrl-A/E", crate::t!("shortcut.home_end")),
+            ("Ctrl-W", crate::t!("shortcut.del_word")),
+            ("Enter", crate::t!("shortcut.run")),
+        ];
+    }
+    // 5. Default — empty input, Input focus.
+    vec![
+        ("Ctrl-O", crate::t!("shortcut.nav")),
+        ("Tab", crate::t!("shortcut.complete")),
+        ("↑", crate::t!("shortcut.history")),
+        ("Enter", crate::t!("shortcut.run")),
+    ]
+}
+
 fn render_status_bar(app: &App, theme: &Theme, frame: &mut Frame<'_>, area: Rect) {
     let key_style = Style::default()
         .fg(theme.fg)
@@ -1855,35 +1924,14 @@ fn render_status_bar(app: &App, theme: &Theme, frame: &mut Frame<'_>, area: Rect
 
     let separator = Span::styled("  ·  ", sep_style);
     let mut spans: Vec<Span<'_>> = Vec::new();
-
+    for (key, label) in status_bar_bindings(app) {
-    let push_shortcut = |spans: &mut Vec<Span<'_>>, key: &'static str, label: &str| {
         if !spans.is_empty() {
             spans.push(separator.clone());
         }
         spans.push(Span::styled(key, key_style));
         spans.push(Span::raw(" "));
-        spans.push(Span::styled(label.to_string(), label_style));
+        spans.push(Span::styled(label, label_style));
-    };
-
-    let submit = crate::t!("shortcut.submit");
-    push_shortcut(&mut spans, "Enter", &submit);
-    let switch = crate::t!("shortcut.switch");
-    let advanced_once = crate::t!("shortcut.advanced_once");
-    let cancel_one_shot = crate::t!("shortcut.cancel_one_shot");
-    let quit = crate::t!("shortcut.quit");
-    match app.effective_mode() {
-        EffectiveMode::Simple => {
-            push_shortcut(&mut spans, ":", &advanced_once);
-            push_shortcut(&mut spans, "mode advanced", &switch);
     }
-        EffectiveMode::AdvancedPersistent => {
-            push_shortcut(&mut spans, "mode simple", &switch);
-        }
-        EffectiveMode::AdvancedOneShot => {
-            push_shortcut(&mut spans, "Backspace", &cancel_one_shot);
-        }
-    }
-    push_shortcut(&mut spans, "Ctrl-C", &quit);
 
     let paragraph = Paragraph::new(Line::from(spans)).style(bar_style);
     frame.render_widget(paragraph, area);
@@ -2582,6 +2630,168 @@ mod tests {
             .expect("hint bottom border present")
     }
 
+    // ---- ADR-0051 (issue #27): context- and state-aware strip ----
+
+    fn key_event(code: crossterm::event::KeyCode) -> crate::event::AppEvent {
+        crate::event::AppEvent::Key(crossterm::event::KeyEvent::new(
+            code,
+            crossterm::event::KeyModifiers::NONE,
+        ))
+    }
+
+    /// The `key` column of the strip's bindings, in order.
+    fn strip_keys(app: &App) -> Vec<&'static str> {
+        status_bar_bindings(app).into_iter().map(|(k, _)| k).collect()
+    }
+
+    /// The full rendered strip text (keys + labels + separators).
+    fn strip_text(app: &App) -> String {
+        status_bar_bindings(app)
+            .iter()
+            .map(|(k, l)| format!("{k} {l}"))
+            .collect::<Vec<_>>()
+            .join("  ·  ")
+    }
+
+    fn hint_text(lines: &[Line<'_>]) -> String {
+        lines
+            .iter()
+            .map(|l| l.spans.iter().map(|s| s.content.clone()).collect::<String>())
+            .collect::<Vec<_>>()
+            .join("\n")
+    }
+
+    #[test]
+    fn strip_default_state_is_nav_complete_history_run() {
+        let app = App::new();
+        assert_eq!(strip_keys(&app), vec!["Ctrl-O", "Tab", "↑", "Enter"]);
+    }
+
+    #[test]
+    fn strip_editing_state_surfaces_readline_keys() {
+        // Input has text (no completion/history transient) → the #29
+        // editing keys (ADR-0049).
+        let mut app = App::new();
+        app.input.push_str("create ta");
+        assert_eq!(
+            strip_keys(&app),
+            vec!["Esc", "Ctrl-A/E", "Ctrl-W", "Enter"],
+        );
+    }
+
+    #[test]
+    fn strip_sidebar_focus_state_is_pane_scroll_input() {
+        let mut app = App::new();
+        app.nav_focus = NavFocus::SidebarTables;
+        assert_eq!(
+            strip_keys(&app),
+            vec!["Ctrl-O", "↑↓/PgUp/PgDn", "Esc"],
+        );
+        // ...and the relationships sidebar is the same state.
+        app.nav_focus = NavFocus::SidebarRelationships;
+        assert_eq!(strip_keys(&app), vec!["Ctrl-O", "↑↓/PgUp/PgDn", "Esc"]);
+    }
+
+    #[test]
+    fn strip_completion_memo_state_is_cycle_cancel_run() {
+        // Drive the real flow: `show ` + Tab leaves a multi-candidate
+        // memo (ADR-0022). The strip must win over the editing state.
+        let mut app = App::new();
+        for c in "show ".chars() {
+            app.update(key_event(crossterm::event::KeyCode::Char(c)));
+        }
+        app.update(key_event(crossterm::event::KeyCode::Tab));
+        assert!(app.last_completion.is_some(), "memo set by Tab");
+        assert!(!app.input.is_empty(), "input non-empty — would be editing");
+        assert_eq!(
+            strip_keys(&app),
+            vec!["Tab/Shift-Tab", "Esc", "Enter"],
+            "completion state wins over editing",
+        );
+    }
+
+    #[test]
+    fn strip_history_navigation_state_is_browse_clear_run() {
+        // Submit a command, then Up to recall it — `history_cursor` is
+        // set, input is the (non-empty) recalled line, no memo.
+        let mut app = App::new();
+        for c in "drop table T".chars() {
+            app.update(key_event(crossterm::event::KeyCode::Char(c)));
+        }
+        app.update(key_event(crossterm::event::KeyCode::Enter)); // submit
+        app.update(key_event(crossterm::event::KeyCode::Up)); // recall
+        assert!(app.is_browsing_history(), "browsing recalled history");
+        assert!(app.last_completion.is_none(), "no completion memo");
+        assert_eq!(
+            strip_keys(&app),
+            vec!["↑↓", "Esc", "Enter"],
+            "history state wins over editing",
+        );
+    }
+
+    #[test]
+    fn every_strip_state_fits_the_eighty_column_budget() {
+        // ADR-0051 §3: the strips are kept lean by construction — the
+        // longest must fit an 80-col status line, so no graceful-drop
+        // machinery is needed. A future over-long strip fails here.
+        let sidebar = {
+            let mut a = App::new();
+            a.nav_focus = NavFocus::SidebarTables;
+            a
+        };
+        let editing = {
+            let mut a = App::new();
+            a.input.push('x');
+            a
+        };
+        for app in [&App::new(), &sidebar, &editing] {
+            let text = strip_text(app);
+            assert!(
+                text.chars().count() <= 80,
+                "strip {} cols > 80: {text:?}",
+                text.chars().count(),
+            );
+        }
+    }
+
+    #[test]
+    fn empty_hint_advertises_advanced_mode_in_simple() {
+        let app = App::new();
+        // Wide width so the pointer never wrap-splits.
+        let text = hint_text(&resolve_hint_lines(&app, &Theme::dark(), 200, 3));
+        assert!(
+            text.contains("`mode advanced` for SQL"),
+            "simple empty hint carries the advanced pointer:\n{text}",
+        );
+    }
+
+    #[test]
+    fn advanced_mode_empty_hint_has_no_mode_pointer() {
+        // ADR-0051: advanced mode shows no mode pointer (users know how
+        // they got there; `help` covers the way back).
+        let mut app = App::new();
+        app.mode = Mode::Advanced;
+        let text = hint_text(&resolve_hint_lines(&app, &Theme::dark(), 200, 3));
+        assert!(
+            !text.contains("mode simple") && !text.contains("mode advanced"),
+            "advanced empty hint carries no mode pointer:\n{text}",
+        );
+    }
+
+    #[test]
+    fn typing_replaces_the_empty_hint_mode_pointer() {
+        // Non-empty input → ambient hint path, not the empty-hint
+        // mode pointer.
+        let mut app = App::new();
+        app.input.push_str("create table");
+        app.input_cursor = app.input.len();
+        let text = hint_text(&resolve_hint_lines(&app, &Theme::dark(), 200, 3));
+        assert!(
+            !text.contains("for SQL"),
+            "no mode pointer once typing:\n{text}",
+        );
+    }
+
     #[test]
     fn clamp_wrapped_truncates_with_ellipsis_past_max() {
         // ≤ max rows: untouched.

tests/it/walking_skeleton.rs

@@ -223,21 +223,30 @@ fn typing_colon_in_simple_mode_flips_prompt_to_advanced() {
 }
 
 #[test]
-fn status_bar_lists_quit_and_submit_in_all_modes() {
+fn status_bar_is_keystroke_only_and_state_aware() {
+    // ADR-0051 (issue #27): the bottom strip is keystrokes-only and
+    // tracks the interaction state. Typed-command words (`:` advanced
+    // once, `mode advanced`/`mode simple` switch) and `Ctrl-C quit`
+    // leave the strip; mode discovery moves to the hint (locked by the
+    // ui.rs unit tests). This test exercises the real render path.
     let mut app = App::new();
     let theme = Theme::dark();
 
-    let simple = rendered_text(&mut app, &theme, 80, 24);
+    // Default (empty input): nav / complete / history / run keystrokes.
-    assert!(simple.contains("Enter"), "status bar lists Enter");
+    let default_view = rendered_text(&mut app, &theme, 80, 24);
-    assert!(simple.contains("Ctrl-C"), "status bar lists Ctrl-C");
+    assert!(default_view.contains("Ctrl-O sidebar"), "strip lists sidebar:\n{default_view}");
-    assert!(simple.contains("mode advanced"));
+    assert!(default_view.contains("Enter run"), "strip lists run:\n{default_view}");
+    assert!(!default_view.contains("Ctrl-C"), "quit dropped from the strip:\n{default_view}");
+    assert!(
+        !default_view.contains("advanced once"),
+        "`:` command word dropped from the strip:\n{default_view}",
+    );
 
-    type_str(&mut app, "mode advanced");
+    // Editing (input has text): the #29 readline edit keys appear.
-    submit(&mut app);
+    type_str(&mut app, "create");
-    let advanced = rendered_text(&mut app, &theme, 80, 24);
+    let editing = rendered_text(&mut app, &theme, 80, 24);
-    assert!(advanced.contains("Enter"));
+    assert!(editing.contains("Esc clear"), "editing strip lists clear:\n{editing}");
-    assert!(advanced.contains("Ctrl-C"));
+    assert!(editing.contains("Ctrl-W del word"), "editing strip lists del word:\n{editing}");
-    assert!(advanced.contains("mode simple"));
 }
 
 // ---------------------------------------------------------------